Improvement in air-distributing pipes for furnaces



A. R Aw s-0N. .Air-Distributing Pipes for Furnaces.

Patented Feb. 3, I874.

TTNIT D STATES PATENT OFFIcn.

ALONZO RAVVSON, OF DES MOINES, IO\VA.

IMPROVEMENT IN AIR-DISTRIBUTING PIPES FOR FURNACES.

Specification forming part of Letters Patent No. 147,022, dated Fel ruary 3, 1874; application filul April 26, 1 3.

To all whom it may concern Be it known that I, ALONZO RAWSON, of Des Moines Iowa, have invented certain Improvements n1 Air-Distributing Pipes for Furnaces, of which the following is a specification:

My invention is an improvement of the airdistributing pipe for furnaces patented July 9, 1872, No.128,864. It consists, first, in making the inside cylinder stationary, with flanges on the ends to close the ends of the outside cylinder; second,in making a graduated series of diagonal slots or lines of perforations in place of the one wide longitudinal slot, and the other smaller slot or str. ight line of perforations; third, in making an opening at the terminus and under side of the fixed cylinder for the purpose of cleaning; fourth, in making the diameter of the outside cylinder large enough to allow the cylinder to hang loosely upon the inside cylinder, and in such a manv ner that it willnot come in contact therewith except on the top surface, and will not clog with ashes and cinders, all as hereinafter fully set forth.

Mydrawing is a miniature perspective view, representing the end of the inner cylinder fastened against the furnace-wall, underneath and near the front end of the grate, and illustrates the construction and operation of my improvement.

A A is a section of the inside fixed cylinder. It may be cast or formed of sheet metal, and vary in diameter and length to suit furnaces of different sizes and forms. a to represent one of the flanges, which stands at a right angle from the end and circumference of the cylinder A. It serves to close the open end of the outside cylinder, and may also be used as a means of attaching the inside cylinder to the wall by driving nails through it. A similar flange or collar is used at the opposite end and for the same purposes. One of them must be movable to allow the outside cylinder to be passed or slipped over the inner. 1 2 3 4 5 6 is a series of graduated diagonal slots or rows of perforations cut in the rear and upper quarter of the cylinder A.

By making these openings diagonal I can distribute air along the entire length of the cylinder fully as well as with the continued longitudinal slots, and by graduating them in size I can equalize the force of the blast along the entire cylinder. When the openings are continuous longitudinal slots, or a series of diagonal or transverse slots of equal size, the pressure and blast will be greatest at the terminus of the cylinder. By a gradual enlargement of the openings from the terminus toward the opposite end, the pressure and dis tribution of air are equalized along the entire line of openings. The same result may be accomplished with openings of uniform size by gradually enlarging the cylinder from the entrance toward the terminus.

b is an opening in the under side and terminus of the cylinder, provided for the pun pose of blowing out ashes and dirt that may fall in through the series of openings on the top. B B is a section of the enlarged outside cylinder, hanging loosely upon the fixed cylinder A. O 0 is a longitudinal slot, corresponding in width with the length of the series of diagonal slots. c is a division of the slot, and indicates how a part of the wall of the cylinder may remain to preserve the form of the cylinder. (1 is a handle on the under side of the cylinder, and serves as a means of turning the cylinder, and also as an indicator to show the volume and direction of the blast. When the handle points-directly downward, the series of openings, 1 2 3 4 5 6, are all entirely open. By turning the outside cylinder and bringing the handle (1 toward the front of the furnace, the series of openings in the inside cylinder may be closed from the top downward, partly or entirely. By this means the volume and direction of the blast can be easily regulated and adapted to the varying conditions of the fire. By turning the outsidecylinder so as to bring the wide slot 0 on the under side, the series of openings in the inside cylinder will be covered, and the opening I) on the under side and terminus will be uncovered. By this means the whole blast can be applied to blow ashes and dirt out through the open ing I). By enlarging the outside cylinder and hanging it loosely upon the inner, so that the two come into close contact only on the top, I provide a means of preventing ashes and cinders from lodging between the walls of the two cylinders, and thereby clogging and locking them together. The annular space between them grows Wider from the top downward, and any particles that fall from the fire and enter that annular space will immediately pass to the under side Without interfering with the turning of the cylinder. hen particles accumulate there sufiicient to produce friction, they can be readily emptied by bringing the slot 0 to the under side.

I claim as my invention- 1. The flanges a, when combined with the cylinder A, as a means of securing the cylinder, and also closing the end of the vacant space between the cylinders A and B.

2. In an air-distributing pipe for furnaces,

the graduated series of openings 1 2 3 4, substantially as described, and for the purposes specified.

3. The opening I) at the terminus of the ALONZO RAWSON.

Witnesses I L. A. CRANE, (l. M. SMITH. 

